TWI250556B - Lithographic apparatus, device manufacturing method, and device manufactured thereby - Google Patents

Abstract

A lithographic projection apparatus with a pre-alignment unit for determining the position and orientation of the substrate, comprising an edge sensor for determining the distance of the edge of the substrate along a measurement axis from an axis of rotation; means for rotating the substrate about said axis of rotation in order to vary the part of the edge of the substrate that coincides with the measurement axis; means for determining, from the determined distances of the edge of the substrate from the axis of rotation and the corresponding angle of rotation of the substrate, the position and orientation of the substrate.

Description

A7 B7 1250556 V. INSTRUCTION DESCRIPTION (彳) The present invention relates to a lithographic projection apparatus comprising: - an illumination system for providing an illumination projection beam; - a support structure for supporting the pattern, the pattern The device is configured to design a pattern of the projected beam according to a desired pattern; - a substrate table for fixing a substrate; and - a projection beam for projecting the pattern on the target portion of the substrate Projection system. The term "patterning means" as used herein generally refers to an incident beam having a patterned cross-section that is consistent with the pattern to be produced in the target portion of the substrate. The term "light valve" is also used in the middle. In general, the pattern will be the same as a special functional layer of the component to be produced in the target portion, such as integrated circuits or other components (described below). Examples of such patterning devices include: - a reticle. The concept of photomasks is well known in lithography, and its types include binary, alternating phase-shift, attenuated phase-shift, and various blends. (hybrid) type of mask. Depending on the pattern of the reticle, the position of such a reticle in the illuminating beam causes selective penetration (in the case of penetrating the reticle) or reflection of the illuminating light on the reticle (in the case of the illuminating beam) In the case of a reflective reticle). When a reticle is used, the support structure will typically be a reticle stage to ensure that the reticle can be secured in the desired position in the incident beam and can be moved relative to the beam if desired. -4- This paper scale applies to China National Standard (CNS) A4 specification (21〇x297 mm)---- 1250556 V. Invention description (programmable mirror array. This type of component is only a κ κ 系 system An addressable matrix table r with a telescopic control layer and a reflective surface, and the basic principle of the 乂 neck device, is a fixed-range 蛣 蛣 ^ ^ ^ £ site of the reflective surface The incident light is reflected into a pair of nine lines, and the unaddressed area is combined with a A i to reflect the incident first into a non-diffracted light appropriate chopper, and the non-diffracted light can be removed from the reflection 2, leaving only The light is diffracted downward; in this way, the beam can be patterned according to the address pattern of the surface of the = addressable matrix. Another embodiment of the mirror-type mirror is a matrix arrangement using a small mirror surface, by Each mirror can be individually tilted relative to an axis by applying an appropriate area Thunder seven or using a piezoelectric actuator. Similarly, the mirror is addressable matrix, so The mirror of the address will have the incident illumination beam in a different way Reflected to the unaddressed mirror; in this way, the beam can be patterned according to the address pattern of the addressable matrix mirror. The required matrix addressing can be done with the appropriate = sub-device. In either case, the patterning device may include one or more programmable mirror arrays. For example, in U.S. Patent Nos. 1,158,296,891 and 1 5,523,193 and 1 patent application, WO 98/38597, More information on such mirror arrays can be found in 〇 98/33096, which is incorporated herein by reference. When using a programmable mirror array, the support structure may be a frame or a platform, for example, Illustrated in the U.S. Patent No. 5,229,872, the disclosure of which is incorporated herein by reference. The scale applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) A7 B7 1250556 V. Description of invention (3). As mentioned above, the support structure may be a frame or a Platform, for example, 'can be fixed or portable as needed. For the sake of simplicity, some parts of the rest of this article will be specifically directed to the reticle and reticle platform. However, the general principles discussed in these examples should be found in the broad article of the above mentioned patterning device. For example, 'a lithographic projection device may be utilized in the fabrication of integrated circuits (ICs) In this case, the pattern device may generate a circuit pattern corresponding to the layer (1:: each layer, and the pattern is imaged on a substrate (tantal wafer) to which a layer of photosensitive material (light group) has been applied. The target part (for example, contains one or more dies). In general, a single wafer will contain the entire network of adjacent target portions after successive illuminations through the projection system one at a time. In current installations, there are two different machine types for pattern processing by means of a reticle on the reticle stage. In one of the lithographic projection devices, each of the target portions is illuminated by simultaneously exposing all of the reticle patterns on the target portion. Such devices are commonly referred to as wafer steppers. In an alternative device - commonly referred to as a step-and-scan and-SCan device, the device is scanned progressively under a certain reference direction ("scanning direction") to illuminate the reticle pattern under the projected beam. The target portion, while scanning the substrate platform in a direction parallel or anti-parallel to the direction; since the projection system usually has a magnification factor (usually less than 1}, the substrate The scanning speed v of the platform will be "multiplied by the scanning speed of the reticle platform. For example, in the US patent case US 6,046,792, more information about such lithographic components can be obtained. 1250556 Invention Description" The method is incorporated herein. In a process utilizing a lithographic projection apparatus, a pattern (for example, in a reticle) is produced on a substrate, the substrate being at least partially exposed to a photosensitive material (resistance) Covered. Prior to this imaging step, the substrate may undergo various treatments such as priming, photoresist coating, and soft bake (s〇ft bake). After exposure, the substrate may be It will undergo other processing 'Post-exposure bake (PEB), development, hard bake and measurement and inspection of the characteristics of the image. The series is treated as a component. For example, 1C, the individual layers are the basis for pattern processing. Then such patterned layers may undergo various treatments such as residual, ion implantation (doping), metallization, oxidation, chemical-mechanical The purpose of grinding, etc., is to polish individual layers. If several layers are required, then the entire process can be repeated for each new layer, or the process of its change. Finally, on the substrate (wafer) A series of components are produced on the top. These components are then separated from each other by techniques like dicing or sawing, so that each component can be mounted on a carrier, in contrast to the pin. Connections, etc. For example, further information on this type of processing can be obtained from McGraw Hill Publishing Co., 1997, by Peter van Zant, "Microchip Fabrication: A Practical Guide to Semiconductor Processing,,, ISBN 0-07-067250-4, which is incorporated herein by reference. For the sake of simplification, the projection system is hereinafter referred to as "lens" However, the term should be interpreted broadly to encompass various types of projection systems, including, for example, refractive optical systems, reflective optical systems, and this paper scale applies to the Chinese National Standard (CNS) A4 specification (210 X 297). PCT) 1250556 V. Description of the invention (5 乂 and Wang diguang (catadi0ptric) system. The illumination system may also include components that operate in accordance with any of a number of design types to redirect the "beam beam' to change shape or control, and such components will hereinafter be referred to as lenses. Furthermore, the lithography apparatus may have two or more substrate platforms (and/or two or more reticle platforms). In this "multiple stage," the component k is never μ. Additional platforms may be used at the same time, or when another or a platform is exposing, one or more The preparation steps are carried out on the platform. For example, a dual-platform lithography apparatus is described in US Pat. No. 5,969, 441 and the entire disclosure of which is incorporated herein by reference. It is necessary to transport the substrate (for example, a wafer) from a predetermined position to the substrate symmetry within the preset range, and must have a known movement and rotational offset from the preset position. The wafer is processed by the wafer 鲚 φ & ^ aligner,, to perform the = Λ alignment unit of the = =, or "the direction of the front aligner,; 曰 ^ 进 ::: The circle is positioned relative to the wafer platform and positioned so that it can be offset within specifications. I and - will emboss an edge or corner of the wafer to the well-known surface = mode with the pre-determined position of the wafer that was previously known to be aligned with the wafer. However, its shortcomings are due to the low precision, very /: the fragmentation of the wafer edge thus further reduces the accuracy: pollution =: the impact of 丨 wear and wafer expansion, can not be measured in Russia ::: , to mark the direction of the wafer), and it is usually limited to (= -8 x 297 mm). This paper scale is suitable for g S home Su (C_ Α 4 specification g 1250556

The wafer size processed. Also known to us is the ability to optically pre-align circular wafers. This method is not suitable for square or rectangular wafers. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for pre-positioning a polygonal substrate thereof which prevents the risk of damage due to chipping and which is faster and more accurate than conventional methods. All of the objects are achieved according to the lithographic apparatus described in the opening paragraph of the present invention, characterized in that the apparatus further comprises a front alignment unit for determining the position and orientation of the substrate in the front alignment unit (four). The method comprises: - means for rotating the substrate along a rotation axis perpendicular to the plane of the substrate; - a contact edge sensor for paralleling the substrate at a range of rotation angles of the substrate The measuring axis of the plane determines the distance from the axis of rotation of the edge of the substrate; • the point at which the at least two major edges of the substrate are determined by the points associated with each edge defined by the determined distance and the corresponding angle Optimum line device; and means for determining the position and orientation of the substrate in the front alignment unit by using the optimum line of the decision; and the front alignment unit is adjustable to determine the position of the polygon, the planar substrate and direction. The advantage of using this device is that it minimizes the risk of damage to the edge of the substrate during the pre-alignment process and the substrate does not require any rotational symmetry. Moreover, even if the corner of the substrate has been damaged or has a notch, the device can accurately determine the position of the substrate and

V. Description of the Invention (In the preferred embodiment of the present invention, the device can be made from: d; to determine the position of the substrate - the position of a corner ... two; the two of the substrate are established to at least eight T § the substrate The corner has already been pointed out that the swept device will be able to determine the location of the damaged substrate corner when the 叫 叫 坏 坏 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 The means for accurately determining the position of the substrate and determining the optimum line may include finding a circle that is most suitable for each side: a circle of adjacent points to predict the distance determined by the distance and angle. Means for the radius of curvature of the edge of the substrate of the four fixed points; the curvature prediction radius determines which point is associated with the corner of the substrate, and is used to determine between the adjacent points associated with the corner Preferably, in a preferred embodiment of the invention, the apparatus further includes a transport device for placing the substrate on the base ridge for use in determining The position and orientation of the substrate The result is such that the substrate is placed on the substrate platform within a predetermined range from a predetermined position and has a known shift (four) rotation offset from the predicted position. A further aspect provides a component manufacturing method comprising the steps of: - providing a substrate at least partially covered by a layer of photosensitive material; - providing an illumination projection beam by means of an illumination system; - providing a The projected beam with a pattern on the cut surface; • The irradiated beam after the pattern is projected onto the photosensitive material layer. The paper size is applicable to the Chinese National Standard (CNS) 八四胡7 (210 X297 mm) 1250556 A7 ---------B7 V. Inventive Note (8) Standard part; characterized in that the pre-alignment unit is determined by the following method before projecting the patterned illumination beam onto the substrate Position and orientation of the substrate: - rotating the substrate along a rotational axis substantially perpendicular to the plane of the substrate; • using a non-contact edge sensor at a plurality of rotation angles of the substrate, The measuring axis parallel to the plane of the substrate determines the distance from the axis of rotation of the substrate edge; - the point associated with each edge defined by the determined distance and the corresponding angle determines at least two masters of the substrate An optimum line of the edge; and - an optimum line using the decision determines the position and orientation of the substrate in the front alignment unit; and the front alignment unit is adjustable to determine the position of the polygon, the planar substrate and the orientation ❶ according to the present invention A further aspect provides a computer program for operating a lithography projection device, the computer program including an encoding device for directing the device to perform the following steps: • calculating the position and orientation of the substrate within the front alignment unit; and - using the calculated The position and direction of the substrate is controlled by a transport device for placing the substrate on a substrate platform within a predetermined position and direction, and having a known offset; The encoding device for calculating the position and orientation of the substrate in the pre-aligned unit includes an encoding device for performing the following steps: A non-contact sensor to receive a first plurality of edge information elements, each -11-- present paper Choi S @ appropriate scale of Standards (CNS) A4 size (21G X 297 Kimiyoshi) ----- 1250556 A7

The data elements are equivalent to the distance between the edge of the substrate and the rotation axis of the front alignment unit; _ receiving a second plurality of data elements, each data element corresponding to the substrate relative to the first plurality of data elements - an associated ^ front alignment unit rotation axis rotation angle; - an optimum line for calculating at least two tamping main edges of the stencil from the first and second data elements associated with each edge; and - « The optimum line calculates the position and direction of the substrate in the front alignment unit; and the front alignment unit is adjustable to determine the position and direction of the polygon, the planar substrate. Although the device of the present invention is used in the context of 1 (3 manufacturing), it should be clearly understood that such devices have many other possible applications. For example, it may be used in the manufacture of integrated optical systems, magnetic memory guidance. And <testing the pattern' liquid crystal display panel, thin film magnetic head, etc. Those skilled in the art will find the term "reticle" used in the context of such alternative applications, " Wafers, or "die" should be in the more general terms "mask", "substrate", and "target portion", respectively. In this document, the terms "radiation," and "beam" are used to cover all electromagnetic radiation, including ultraviolet radiation (eg, wavelengths 365, 248, 193, 157 or 126). Nm) and EUV (extreme ultra-violet radiation, eg wavelength range 5-20 nm), and particle beams, such as ion beams or electron beams. Zhang scale applies Chinese National Standard (CNS) A4 specification (210 X 297 mm)

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1 is a lithographic projection apparatus according to an embodiment of the present invention; FIG. 2 is a schematic diagram of a front alignment unit according to the present invention; FIG. 3a is not the edge sensor coordinate system and the Marking the relationship between the sensor coordinate system; Figure 3b shows the geometric wafer coordinate system; Figure 4 is a step for determining the position and orientation of the wafer in the pre-aligner. Figure 5 shows the offset between the edge sensor coordinate system and the geometric wafer coordinate system; and Figure 6 is used to determine the edge sensor coordinate system and the geometric wafer coordinate system The steps between the offsets. In the drawings, the same reference numerals indicate the same parts. County Embodiment 1 FIG. 1 shows a lithographic projection apparatus according to a specific embodiment of the present invention. The apparatus comprises: • an illumination system Ex, IL· for providing an illumination projection beam PB (e.g., uv illumination). In this particular example, it also includes an illumination source la; a first object platform (mask a MT, which is provided with a reticle holder for fixing the reticle MA (for example, a main reticle), and is connected to the first positioning device for accurately placing the reticle at a position relative to the PL; a two object platform (substrate platform) WT configured with a substrate holder for fixing a substrate W (for example, a photoresist wafer having been coated with a photoresist), and connected to a second positioning device for accurately placing the substrate Relative to the position of the PL; -13· This paper scale applies to the National Standard for Towels (CNS) A4 specification (21G X 297 public) 'A7 B7 1250556 V. Description of invention (11) • A projection system ("lens, , PL (for example, a lens group, a catadioptric or reflective system) for imaging a portion of the reticle MA that is illuminated by the target portion C of the substrate w (eg, including one or more dies). As shown, the device is transmissive (ie, has a transmissive mask. However, for example, it may also be reflective (with a reflective mask). Alternatively, the device may use other types of patterning devices, such as the type of programmable Mirror array. A light source LA (such as a mercury lamp, an excimer laser, an ion discharge source, or an electron grab) produces an illumination beam. For example, the beam may be fed directly or through an adjustment device such as a beam amplifier (beam eXpande) 〇Ex ' is fed into an illumination system (illuminator). The illuminator IL may include an adjustment device am for setting the intensity distribution of the outer and/or inner rings in the beam (generally referred to as σ). - outside and σ-inside). In addition, it usually includes various other components, such as an integrator and a concentrator C. In this way, the beam 射 incident on the reticle will have the desired Uniformity and intensity distribution. It should be noted that the light source LA in Figure 1 may be placed in the casing of the lithographic projection device (for example, as most of the mercury bulbs are used as In the case of the light source LA), but it may also be spaced apart from the lithographic projection device, and the resulting illumination beam will be directed onto the device (for example by means of a suitable guiding mirror); when the light is the original LA When it is an excimer laser, it will usually be the latter case. The invention and the scope of the patent application cover two situations.

In essence, the light beam PB intercepts the photomask MA -14 fixed by the mask platform MT - the paper scale is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 1250556 A7 B7 V. Invention Description (12 ). After passing through the reticle MA, the light beam PB passes through the lens &amp; which will focus the light beam PB in the target portion c of the substrate w. With the first positioning device (and the interference measuring device IF), the substrate platform WT can be accurately moved, for example, to position different target portions c on the path of the beam pB. Similarly, for example, after the reticle MA is mechanically removed from the mask library, or during scanning, the first locating device can be used to accurately position the reticle MA relative to The path of the light beam PB. Generally, the movement of the object platform mt, WT is achieved by a long-range (l〇ng-str〇ke) module (path positioning) and a short-stroke module (detail positioning). Not clearly depicted. However, in the case of a wafer stepper (as opposed to a step-scan device), the mask platform MT may only be connected to a short-range actuator or may be fixed. The device depicted may be used in two modes: ^ Step mode, basically the reticle stage MT remains stationary, and the entire reticle image is fully projected at a time (ie, a single "flash" ,, in a target part C. Then the substrate platform WT will move in the X and / or y direction 'so the beam PB can illuminate different target parts c. 2 · Scan mode, basically the same The situation, but will not expose the specific target part C to a single "flash,". Instead, the reticle stage MT can be moved at a speed V in a specific direction (so-called "scanning direction," for example, y direction), so that the projected beam PB is scanned over the reticle image; The substrate platform WT will move in the same or opposite direction at the same speed V=Mv, wherein the magnification of the lens PL is passed (through L __________ 15 · National Standard for Paper (CNS) Μ Specifications ((10) 〉 <Novogong Love) Binding! 25〇556

Often '_/4 or 1/5). In this way, a larger target portion C may be exposed, but the resolution will not deteriorate. The apparatus further includes a pre-aligner, for example, mechanically separable from the substrate platform to prevent the front aligner from transmitting any shock to the substrate platform. - Substrate handling H, such as a wafer handling robot, for transporting the wafer to the pre-aligner. The substrate carrier then transports the wafer to the substrate platform WT. The substrate carrier may be the same as the one that transports the wafer to the pre-aligner, or it may be a second substrate carrier. To ensure that the displacement accuracy is not lost, the substrate carrier may be in a fixed position relative to the front aligner. Alternatively, the substrate carrier may be mechanically isolated from the front aligner during movement. In this case, an alignment unit is placed prior to picking up the wafer, and the substrate carrier is temporarily coupled to the pre-aligner to define its relative position to the front aligner. One such system is found, for example, from Ep-1 052 548-A2, which is incorporated herein by reference. The pre-aligner can utilize, for example, an air carrier to support the wafer, which only requires a limited mechanical contact to fix the position of the wafer and, if necessary, move. The pre-aligner can also serve several other functions. The gas in the beta helium carrier can be heated or cooled to help stabilize the temperature in the wafer. The gas may be inflated and then gradually deflated from the gas deposited on the wafer and it may be filtered to blow away any contaminants from the underside of the wafer. All uses reduce the likelihood of damage to the crystal and help improve positioning accuracy. For example, one such pre-aligner can be found in EP-1 05 2 546-Α2, this -16- paper scale applies to the Chinese National Standard (CNS) Α4 specification (210 X 297 DON)

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A7 B7 1250556 5. Inventive Description (14 is incorporated herein by reference. As shown in Figure 2, the front aligner of the present invention includes a wafer support 1 for axis RA relative to the front aligner Rotating the wafer W and moving the wafer in a plane parallel to the wafer, an edge sensor ES is used to determine the distance between the edge of the substrate and the axis RA of the plane of the plane of the wafer (hereinafter referred to as a radius), and a mark sensor MS is used to determine the position of the mark on the surface of the wafer. 'When the wafer W is transported from the substrate carrier to the front aligner, it will be on the wafer Any and unknown position in the support, so the pre-aligner must accurately determine the position and orientation of the wafer. Four coordinate systems must be used for this purpose. Two of them, the edge sensor coordinates The system ESCS and the mark sensor coordinate system MSCS are fixed relative to the pre-aligner. The remaining two, the geometric wafer coordinate system GWCS and the wafer coordinate system WCS are respectively relative to The geometry of the wafer and The mark on the wafer is fixed. Figure 3a shows the relationship between the edge sensor coordinate system ESCS and the mark sensor coordinate system MSCS. The edge sensor coordinate system is based on its X axis. That is, the axis of the pixel passing through the rotation axis RA of the front aligner and the edge sensor ES farthest from the rotation axis RA is defined. The Y axis is an axis perpendicular to the X axis, and Passing through the rotation axis RA of the front aligner. When placed in the front aligner, both axes are located in the plane of the wafer. The X axis of the mark sensor coordinate system is passed through The rotation axis RA of the pre-aligner and the axis of the set point in the mark sensor MS. _ -17- This paper size applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 1250556 A7 B7 V. Inventive Description (15) The marking sensor MS is configured in such a manner that the edge sensor coordinate system and the individual axis of the marking sensor coordinate system have a predetermined angle C6 (for example, brother , 60°). In the end, because the edge sensor ES and the marking sensor MS are installed The relationship of the difference tolerance value, so there will be a small offset, C60ffset. Therefore, the overall angle between the axes should be C6 + C60ffset. The C60ffset may have been decided during the calibration procedure. Figure 3b does not. The geometric wafer coordinate system Gwcs. The axis of the GWCS is parallel to the edge of the wafer W, in this case it is a square. The origin of the GWCS is the geometric center of the square wafer. If there is a notch N For example, it may be in the fourth quadrant Q4 of the coordinate system. The wafer coordinate system WCS is defined by a particular mark, such as the position of the reference point ' on the wafer surface. Therefore, there is an offset between the geometric wafer coordinate system and the wafer coordinate system that is constant for each individual wafer. The position shown in Figure 4 determines the position and orientation of the wafer w in the pre-aligner. When the pre-aligner accommodates the wafer, the wafer is rotated by 3 60. The edge sensor ES, which in this embodiment is a charge coupled device, will take two hundred values (referred to as CCD values). Obviously, the invention is not limited to 200 CCD values, and more or less CCD values can be obtained. Then the CCD will be converted into a radius value matrix! Each is associated with the angle at which the measurement is taken. In this example, "radius," refers to the distance from the axis of rotation RA of the pre-aligner to the point on the edge of the wafer as determined by the edge sensor ES. Therefore, the crystal Each amount on the edge of the circle

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A7 B7 1250556 V. INSTRUCTIONS (16) The measuring points are characterized by the columnar coordinates in the edge sensor coordinate system. From these values, the relationship between the edge sensor coordinate system and the geometric wafer coordinate system, or "offset vector" (see below) can be determined. As shown in Figure 5, the relationship is characterized by two The distance r between the origins of the coordinate systems, and the angle of rotation th between the ESCS and the GWCS, for clarity, r will be represented by GWCS_ESCS_r_offset, and th will be represented by GWCS_ESCS__th_offset. Whether the circle W is within this particular acceptable range of positions (ie, comparing GWCS_ESCS_r__offset to a predetermined threshold). For example, the acceptable offset may be within 0.5 mm. If the wafer Without being within this particular limit, it is possible to use the wafer support to move the wafer to reposition its center. The measurement step is then repeated for the new location. This cycle can be repeated until the wafer is repeated. W is within the specified range of positions. If the wafer has a notch N, then the direction of the notch in the edge sensor coordinate system ESCS may be determined ( This will be explained further below. However, it is also possible to determine the direction of the notch before the pre-alignment. The direction of the notch in the edge sensor coordinate system, GWCS-ESCS-theta, refers to the system The direction of the notch found in the geometric wafer coordinate system GWCS after combining the GWCS_ESCS_th_offset. It is generally convenient to obtain the directions in the marker sensor coordinate system. Mode conversion: GWCS-MSCS_theta=GWCS-ESCS_theta+(C6+C60ffset) -19- This paper scale applies to China National Standard (CNS) A4 specification (210X297 mm) A7 B7 1250556 V. Invention description (17) GWCS_MSCS—th— Offset=GWCS—ESCS_th an offset+(C6+C6〇ffset) Note that because the marker coordinate system overlaps the origin of the edge sensor coordinate system, GWCS_MSCS丄offset=GWCS_ESCS丄offset is to explicitly indicate the crystal The position and orientation of the features in the circle W (marked sensing coordinate system) can be the difference between the geometric wafer coordinate system and the wafer coordinate system, ie WCS_GWCS__off Set vector, added to the vector position of the geometric center of the wafer in the marker coordinate system at the angle GWCS_MSCS_th_offset, which is the length vector of GWCS_MSCS_r_offset. The system shown in Figure 6 determines the geometric wafer coordinate system and the edge sense. The steps required for the vector offset between the coordinate systems of the detector. The first step is to predict the radius of curvature of the wafer edge for each measurement point in the edge of the wafer. This can be calculated using the points on either side and finding the circle that best fits the three points. Then, by comparing the curvature radius value with the preset threshold value, the measurement points can be classified into "straight line", "circle" or "other". In this phase, points that are not classified as "straight lines" are rejected. Next, the edge sensor coordinate system ESCS is split into four quadrants and the measured points in each quadrant are compared. Assuming that the offset of the wafer does not exceed a quadrant of the width of the wafer, i.e., does not exceed a single quadrant, each quadrant will contain one of the corners of the wafer. Therefore, the measurement point with the largest radius value in each quadrant can be regarded as a "corner point". After confirming the four "corners", the remaining measurement points between adjacent corners will be regarded as a straight line and then the -20- paper size of the wafer can be regarded as the Chinese National Standard (CNS) A4 specification ( 210 X 297 mm) 18 1250556 V. The invention describes the edge. These measurement points can be converted into flute + &amp; + in the ESCS, determined by the edge sensor coordinate system, and the standard minimum line method can be used for each of the two, and the optimal line of the edge line of the mother bar is y=AX+ b. In the point 盥兮JL ^ %, the distance variation between the two edges of the mother strip is analyzed. Any point beyond that except:! The points must be removed. If it is ticking = point = critical value in this step, for example, the critical value can be assumed to be if the point is removed: Γ: divide? Then, the program must be repeated until there is no tick &amp; viewpoint, when the number of points that are ticked in this step is lower than the limit value, the position of "corner," can be determined. After the four edge lines, the straight lines can be extrapolated, and the four points that meet the condition (the closest to the origin are the 4th parallel intersections that are parallel lines) The angle 'Lo" of the circle w is defined. Please note that if the wafer has a notch, then the corner found at the corner of the notch will be located in the corner where the notch was found. Alternatively, the corners used may be the "corners" found in the maximum radius within each quadrant in the subsequent program for finding the edge line. In this case, it is not necessary to find all four corners. If one of the corners cannot be confirmed, it can be inferred from the position of the other corners. Then, the four corners can be used to find the edge sensor coordinate system ESCS and the geometric wafer coordinate system (;}々(:3 Offset The average of the corner locations is the geometric center of the wafer (which is the origin of the geometric wafer coordinate system). Therefore, r can be defined, as also referred to above as GWCS-ESCSj-offset. The direction of each line of the corners - 21 - The paper size is suitable for the country @家标准(CNS) A4 specification (21GX297 public) 5. The invention description (19 # Γ Γ sentence value is th+45, which makes th The angle of rotation between the Escs and the gwcs·^ is also referred to as GWCS-ESCS-th-offset as described above. The square wafer may be limited to only one (5) of the four corners. Assuming that the wafer is limited to the side of the wafer to be exposed with a ::: direction, then by judging which corner the notch is located, the direction of the notch of the square wafer can be determined early. It may be decided in the previous step or it is decided at this time to determine whether the found corner has a notch. The threshold can be set for the size of the notch to avoid finding an incorrect false because the corner is damaged. Notch. Concave, the measurement may be determined in the front aligner After the position and orientation of the wafer is taken out, or 'it may be performed in the step before the pre-alignment, the wafer will be quickly scanned to determine the position of the notch. Then Accurate wafer center positioning and position and orientation are determined. In some embodiments, 'the use of a non-notched pre-positioning wafer' can preserve the origin of the wafer without having to perform a concave Steps: The above method is for a substrate having four sides and four corners (one of which may be subjected to a notch removal process), that is, a square or rectangular substrate. The method may be adjusted after 35' After that, for example, a different number of "corner points a" can be used in other polygons. 8 All points 5 Although specific embodiments of the invention have been described above, it will be appreciated that the actual application of the invention may be beyond the scope. -twenty two-

This paper scale is suitable for the SS standard (CNS) A4 specification (210X297 public S 1250556 A7 B7 V. Invention description (21 RA axis MSCS mark sensor coordinate system ESCS edge sensor coordinate system GWCS geometric wafer coordinate system N concave Port Q1 first quadrant Q2 second quadrant Q3 third quadrant Q4 fourth quadrant

Binding -24-This paper scale applies to China National Standard (CNS) A4 specification (210 X 297 mm)

Claims (1)

8 8ft A BCD 5 contains secret 116147 patent application meaning Chinese application patent range replacement wood shirt 3萆3) 6. Patent application scope 1. A lithography projection device, comprising: - an illumination system for providing illumination of a projection beam a support structure for supporting the pattern device, the pattern device is configured to design a pattern of the projected beam according to a desired pattern; - a substrate platform for fixing a substrate; - a projection beam for the pattern a projection system at a target portion of the substrate; wherein the substrate further comprises a front alignment unit for determining a position and a direction of the substrate in the alignment unit, comprising: - perpendicular to the permeation a device for rotating the substrate by the rotation axis of the substrate plane; a non-contact edge sensor for determining the axis of the substrate parallel to the plane of the substrate at a rotation angle of the substrate a distance between the axes of rotation of the distal edge of the substrate; - for determining at least two of the substrates by using points associated with the parent edges defined by the determined distance and the corresponding angle Means for selecting the optimum line of the main edge; and - means for determining the position and orientation of the substrate in the pre-aligned unit by using the optimum line of the decision, and the pre-alignment unit is adjustable to determine the polygon, the planar substrate Location and direction. 2. The lithographic projection apparatus of claim 1, wherein the means for determining the position and orientation of the substrate determines the position of at least one corner of the substrate from the intersection of the two optimum lines. 3. For the lithographic projection apparatus of claim 1 or 2, the paper size applies to the Chinese National Standard (CNS) A4 specification (210 x 297 mm). The means for determining the optimum line comprises: 1 means for finding the radius of curvature of the substrate edge of each point defined by the determined distance and angle by finding a circle that best fits each point and each adjacent point on either side; Means for determining which point is associated with the corner of the substrate using the curvature prediction radius; and means for deciding the optimum line of the point between the adjacent points determined to be associated with the corner. 4. The lithographic projection apparatus of claim 1 or 2, wherein the means for rotating the substrate rotates the substrate 360. And the non-contact edge sensor determines the distance between the substrate and the rotating shaft by a preset number of times during the rotation. The lithographic projection apparatus of claim 1 or 2, further comprising a conveying device for conveying the substrate from the front alignment unit to the substrate platform; wherein the conveying device uses the same The structure of the device for determining the position and orientation of the substrate is placed on the substrate to be disturbed by a pre-δ positional distance within a predetermined range and has a known movement and rotational offset from the predetermined position. 6. The lithographic projection apparatus of claim 1 or 2, wherein the non-contact edge sensor is an optical edge sensor. 7. A method of fabricating a semiconductor device, comprising the steps of: - providing a substrate at least partially covered by a layer of photosensitive material; - providing an illumination projection beam by means of an illumination system; - providing a pattern on the slice thereof by means of a patterning device Projection beam; This paper scale applies to China National Standard (CNS) Α4 specification (210X297 public love) 1250556 AB c D ----——_ Sixth, the scope of application for patents - the target part after the processing of the pattern; the first shot is projected onto the layer of photosensitive material, which is characterized by the processing of the pattern Before the illumination beam is projected on the substrate, the position and direction of the substrate in the soap element are aligned by using the following formula: ~ The solid axis rotates the substrate perpendicular to the rotation axis of the substrate plane, and - uses one The non-contact edge sensor is configured to determine a distance from the axis of rotation of the substrate along a measuring axis parallel to the plane of the substrate at a plurality of rotation angles of the substrate; - utilizing the determined distance and The point associated with each edge defined by the corresponding angle determines an optimum line of the at least two main edges of the substrate: and - determining the position and direction of the substrate in the pre-aligned unit by using the determined optimal line; and the front The alignment unit can be adjusted to determine the position and orientation of the polygon, the planar substrate. 8. A semiconductor element manufactured by the following method. Providing a substrate at least partially covered by a layer of photosensitive material; - providing an illumination projection beam by means of an illumination system; - providing a projection beam having a pattern on its slice using a patterning device; - irradiating the patterned illumination beam Projecting on the target portion of the photosensitive material layer; characterized in that the substrate in the front alignment unit is determined by the following method before the patterned irradiation beam is projected onto the substrate. National Standard (CNS) A4 size (210X 297 mm) 8 8 8 8 AB c D 1250556, patent application range board position and direction: - rotate the substrate along a rotation axis substantially perpendicular to the plane of the substrate; - use a non The contact edge sensor is configured to determine a distance from the axis of rotation of the substrate edge along a measuring axis parallel to the plane of the substrate at a plurality of rotation angles of the substrate; - utilizing the determined distance and the corresponding angle The defined points associated with each edge determine the optimal line of at least two major edges of the substrate: and - the optimal line using the decision Position and direction of the substrate in the pre-alignment unit; and adjust the pre-alignment unit for determining the position and orientation of the polygon, the plane of the substrate. 9. A computer readable recording medium comprising a computer program for operating the lithography projection apparatus, the computer program comprising encoding means for directing the apparatus to perform the following steps: - calculating the position of the substrate in the front alignment unit And direction; and - using the calculated position and orientation of the substrate to control a transport device for placing the substrate on a substrate platform within a predetermined range of positions and directions, and having a known offset The encoding device for calculating the position and orientation of the substrate in the pre-aligned unit includes an encoding device for performing the following steps: - receiving the first plurality of data elements from a non-contact edge sensor , each of the lean elements is equivalent to the distance between the edge of the substrate and the axis of rotation of the front alignment unit; -4 8 8 8 8 AB c D 1250556 6. Patent application scope - receiving the second plurality of data elements, each data The elements are each equivalent to a rotation angle of the substrate relative to a rotation axis of the front alignment unit associated with one of the first plurality of data elements; Calculating an optimum line of at least two main edges of the substrate in each of the first and second data elements associated with each edge; and calculating a position and a direction of the substrate in the pre-aligned unit from the optimum line; and the front The alignment unit can be adjusted to determine the position and orientation of the polygon, the planar substrate. This paper scale applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm)